Japan’s growing legion of geeks, once derided as unsociable misfits, has become a significant force of spenders whose financial clout is expected to keep growing, a research institute has found.

The results are likely to prompt businesses to develop new products targeting the mostly male geeks, or “otaku” in Japanese, who are noted for spending every last yen on the hobbies they pursue with a single-minded passion.

According to a survey by Nomura Research Institute (NRI), a Tokyo think-tank, otaku — known for their obsession with aspects of pop culture such as comics, computer games and electronics — now number 1.72 million nationwide and power a market worth more than 400 billion yen a year.

The depths of the world of geeks remain largely unplumbed.

“We made many new discoveries,” think-tank spokesman Nomura said. “The biggest surprise was finding that there are actually five different sub-categories of geeks that cut across the lines of all their interests.”

The largest such group, accounting for 25 percent, are closet otaku whose wives and children give them little time to openly pursue their beloved pastimes.

“These people are pressured by the need to support a family and tend to conceal their obsession,” the institute said in a press release. “They can accumulate money only slowly and secretly for their hobbies.”

Other sub-categories include those obsessed with the Internet and “proselytising geeks,” who try to get others to join them in their obsession.

Gee, we’re not like this. Are we?